Rock drill



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Fil'd June- 1, 19123 r v 2 Smets-snm 1' gwuenhu A/ l/ama/vaac/v/ @Walnut Jan. 6, 1925'.

Y. YAMANOUCHI ROCK DRlLL d subjectofthe Fi'nperorlof Japan, and aresispecification.

Patented dan. 6, 1925,I

YUJ I YAIVIANOUCHI,

rarest OFFICE.

or KYo'ro, JAPAN.

Boex DRILL.

`iyAmilieation filed June 1,-

To all eotvom'z't may concern v#Be itjknown that I, YYUJI YAMANoUcHi, a

dent offNo. 164, '4-choi'ne, Kiyoinizu, Shimo- Kyoku, Kyoto,"-Empire of' Japan, have invented a new and useful Improvement in` 4Rock Drills, of whichl `the following is a This inventionrelates to a rock drill in which the-reaction on a, revolving hammerY produced by' striking thereof against an an- `vifl 4headV is utilized to operate va lever which 'oscillates apawlyengagingin a ratchet wheel fixed' on the anvil, 'the latter thus being revolved. y

'The "object ofthis invention is to 'obtain an exact rotation of Athedr'illfloit so that the operation is done in a safe and easy manner.

i' Thisinvention willbe readily understood by reference tothe accompanyingdrawings inwhich:

Fig. 1 is a general :section'al'side view,

Fig. 2 is a plan view,

Fig. 3 shows a connection of a pawl and a ratchet,

Fig. 4 is a side elevation of a connection of a hammer and a lever, partly being in section, and

Fig. 5 is an end view thereof.

Like numerals refer to like parts in these drawings.

Referring to the drawings, 1 designates a base on which a carriage 2 is slidably fitted. The carriage is provided with a raised frame 3 on which a shaft 4 is transversely mounted to be revolved by a flexible shaft from any suitable prime mover. 5 designates a hammer bearer formed segmentally which is bent and longitudinally extended at its outer edge to form the shape of an L turned upside down in cross section as shown in Figs. 1, 4 and 5. The hammer bearer is also provided with an inclined hammer seat 6 having increasing thickness from one end to another by which a hammer 7 is prevented from reversal because the reaction on the hammer produced by striking thereof against an anvil head is arrested by said seat as shown in Fig. 5. This invention is to utilize the reaction to rotate a ratchet wheel fixed on an anvil 8 so that a drill bit is regularly turnedl in consequence of the regular reacting action on the hammer. The hammer 7 is bored at one end in which an eccentric plate 1.923.y serial No.- M2349.

9 fixed onor extendedifr'om.thei-hhaft Lis fitted. Upon revolution lofthe sliaftflllthe hammer Amay 'rotate with -the V'having'.

centrifugal force. However',"as soon'l faslthe hammer strikes the head 'of the anvil," it partly is returned by reactiontill engaging inthe hammer` seat. Thus, the hammer `engag-ingv in'said `seat passes overvthehe'adof the anvil.` The eccentric plate. is .provided 4 with an 'oblique guideslot 1Q circumferentially about fone half ofits whole periphery. In clase offthe vnormal 'revolution the hammer 7 isf positioned on one'side of theeccenf,

tric plate and is made by theguide piece {engaglngjin the slot 1() to remain'on onejendof 'the'slot as showny in Figj4. But,"in reversal, the hammer is forwardly'shifted'totheopposit'efside'of the eccentric plate 7 by means ofthe'guide piece guided in the guide slot. 11 designates an operating plate fitted on the shaft "slidable lengthwise, say, by means fof a "feathe'rkeyi Said operating 'plateispiovided with an extension or an arm 12 which is adapted for engagement against a side of the hammer. Then it will be clear that the operating plate is laterally moved by the lateral motion of the hammer. 13 is a lever pivoted at its middle on an anvil holder 14 of the carriage. The lever is adapted. to contact with the end surface of the operating plate 11 at one end and is formed a fork at anotherL end. The fork endembraces an upper portion of a pawl frame 15 which is loosely iitted on the anvil 8 and projected up through the -anvil holder. From the pawl frame, a pawl 16 is hung radially around which a spiral spring 17 is wound for obtaining proper engagement of the pawl with a ratchet wheel 18. By reversal of the hammer, the pawl is driven circumferentially to cause the ratchet wheel to turn. In other words, by reversal of the hammer due to reaction, the hammer is shifted laterally by the slot 10, and consequently the operating plate is cooperatively moved laterally and the lever is swung so that the ratchet wheel, the anvil and a drill bit 19 are turned in turn. To prevent opposite revolution of the ratchet wheel another pawl 16 is provided in any suitable manner. In the present case the anvil is provided with a water chamber 20 at any` suitable portion thereof. Cold water is inductedtherefrom through a duct 21. to the end of the drill bit.

This invention is characterized by this thatthe revolution of the anvil is produced by utilization of the reaction on the hammer. Therefore, the drill is turned only after striking of the hammer so that it is most adapted for safe operation. Further the reverse movement of the hammer caused by the reaction is limited so that the feed of the drill results at a constant rate.

I-Iaving now described and ascertained the nature of this invention in what manner the same is to be performed, I declare thatv f connecting with the ratchet wheel, and a reciprocating platepositioned between said hammer and the other end of the-lever, rib means cooperating with said hammer, Whereby to give the hammer a lateral movement on rebounding from striking the anvil, the lateral movement of 'the hammer, acting through said reciprocating plate, causing a partial rotation of the anvil, after each working stroke of the hammer.

2. A rock drill comprising, a base, an anv vil mounted on the base, a hammer mounted on the base for striking the anvil, and connecting means between the anvil and the hammer, the hammer acting directly on the connecting means to cause a partial rotation of the anvil after each Working stroke, said hammer being loosely mounted on an eccentric, and the eccentric being keyed to a drive shaft on said base, said connecting means comprising, a ratchet wheel keyed to said anvil, a lever pivoted to thevbase, one end of the lever operatively connecting with the ratchet wheel, and a reciprocating plate positioned between said'hammer and the other end of the lever, rib means cooperating with said hammer, whereby to give the hammer a lateral movement on rebounding from striking the anvil, the lateral movement of the hammer, acting through said reciproeating plate causing a partial rotation of the anvil, after each working stroke of the hammer. Y

, In testimony whereof I aflix my signature inpresenceof two witnesses.

YUJ I YAMANOUCHI. Witnesses:

W. EBLHORAK, IoHmo LUzUKI. 

